Can’t set up Wahoo Kickr?? (Help)

Picked up a Wahoo Kickr V5 off Facebook Marketplace and I’m trying to set it up with my Canyon Aeroad CF SLX running SRAM Force eTap AXS 12-speed (10–33 cassette)

1. Do I actually need to switch the cassette on the trainer?
   I have a spare SRAM 10–28 XDR cassette from my bike. Can I put that on the Kickr?

2. If yes… how do I actually remove the current cassette?
   I saw someone say “just pull the freehub off” but mine does not come off.
   I removed the end cap, but the freehub/cassette assembly seems stuck on the axle.
   Not sure if I’m missing a step or if this Kickr is different.

3. Do I need a special freehub body?
   If I need to run XDR, do I have to buy the Wahoo XDR freehub first, or can I install my SRAM cassette on the existing one?